• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.368-376
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• 2004

The estimation of the diffusion coefficients of the Gaussian plume model and the release rate by assimilation of tracer-gas measurements on Younggwang site was tested. Diffusion coefficients were modified by linear programming of both the measurements and the simulated using the Gaussian plume model. The application of the modified diffusion coefficients improved the prediction ability of the Gaussian plume model on both 3 km and 8 km arc lines. And, the release rate of tracer gas was estimated using least squares method. The optimal source rate was estimated by minimizing the errors between the measured concentrations and the computed ones by the Gaussian plume model. The obtained release rate showed a good agreement with the real release rate of the Younggwang experiment in 24%.

• Journal of the korean Society of Automotive Engineers
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• v.5 no.2
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• pp.41-47
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• 1983

The analysis shows that the variation of maximum pressure of the cycle, rate of hear release, rate of mass burned, and combustion delay are influenced by the inlet air humidity in the spark-ignition engine. The quantitative combustion delay can be obtained from the rate of mass burned. Also, the variation of time loss and effective compression ratio with the change of inlet air humidity are dominated by the development of rate of heat release.

• Fire Science and Engineering
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• v.25 no.2
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• pp.88-94
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• 2011

Heat release characteristics of live fire load are an important parameter for performance oriented fire safety design of a building. While investigations have been carried out on the fire load and its burning behavior in office, residential and commercial buildings and so on, little effort has been paid for the rational treatment of fire load in bookstore. In this report, burning behavior of typical combustible objects in bookstore are studied by measuring heat release rates of bookshelf with book. Based on the results, it has reviewed fire safety when a fire accident occurs on the large bookstore and suggested peak heat release rate per burning surface, fire growth rate, etc of the live fire load required for fire safety design in bookstore.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.2
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• pp.192-203
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• 1999

This paper deals with the order release problem for minimizing weighted earliness and tardiness as well as Work In Process (WIP) in dynamic job shop environments. A newly designed hierarchical order release mechanism is developed for efficient real-time control of the earliness/tardiness and WIP. The hierarchical order release mechanism consists of the order release plan and the order release control which is composed of two procedures. The experimental results show that the proposed order release mechanism is superior to other four order release mechanisms under overall simulation conditions of utilization rate, due-date allowances, and earliness/tardiness cost structures. In addition, the difference of total cost among the four dispatching rules is much more reduced in the proposed order release mechanism than in other release mechanisms.

• Journal of Pharmaceutical Investigation
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• v.30 no.1
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• pp.27-32
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• 2000

Various release test methods have been applied for the evaluation of nicotine release in vitro from commercial patches. However, whether and how the release data reflect the permeation of nicotine across the skin, is not fully elucidated. To predict in vivo bioavailability from in vitro release tests, correlation between in vitro release and in vitro skin permeation was assessed in the present study. Release of nicotine from three commercial patches was measured for 24 hours under nine experimental conditions which were classified depending on the apparatus (i.e., paddle over disk, cylinder and reciprocating holder) and dissolution media (i.e., phosphate buffer pH 7.4, water and the 1 % phosphoric acid pH 1.5). In vitro permeation of nicotine from the patches across the human cadaver skin was also measured using a diffusion cell. The release of nicotine was better explained by the Higuchi's equation rather than by the first order rate equation. Correlation between the release rate and the in vitro skin permeation differed among the patches. However, in general, the cylinder method, in which water is used as a dissolution medium, showed the highest correlation among the nine release test conditions.

• The Journal of Korean Physical Therapy
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• v.28 no.3
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• pp.201-204
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• 2016

Purpose: The purpose of this study was to compare the immediate effects of alternative treatment methods in lowering the blood pressure and pulse of prehypertensive patients. Methods: A total of 48 prehypertensive patients were randomly divided into 4 groups of 12 patients and each group received a different intervention. The control group was made to rest, the heat pack (HP) group received heat pack treatment, the ultrasound (US) group received an ultrasound massage, and the myofascial release (MFR) group received myofascial release. The blood pressure and pulse rate were measured before and after intervention. Results: Following intervention, the patients of the MFR group showed a decrease in systolic pressure, diastolic pressure, and pulse rate. Although blood pressure was similar in all groups, a significant decrease in pulse rate was seen in the MFR group compared to others. Conclusion: The application of MFR was shown to be an effective method for lowering the blood pressure and pulse rate in prehypertensive patients.

• KSBB Journal
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• v.5 no.4
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• pp.377-382
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• 1990

The characteristics controlled drug release have been studied for biodegradable polymer matrix. Polymer matrix was prepared from glycerine, prednisolone and dextran. Mathematical analysis of the data showed that the release behavior actually conformed to the Higuchi's diffusion controlled model. The release time was increased as drug loading doses increased, whereas decreased as glycerine concentration increased. The release rate did not change by varying molecular weight of dextran.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.206-212
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• 2009

Chemical behaviors of each surface material for interior facilities affect to fire initiation and growth in general fire situation. These chemical behaviors were characterized by thermal properties (Heat release rate, Pyrolysis rate, specific heat, etc) which could be derived from experimental test. Especially, Heat release rate which indicates aspect of fire size is one of the most important property to asses fire hazard and protection needs. The cone calorimeter test (ISO 5660) has recently assumed to a dominant role in bench scale fire testing to obtain the Heat release rate of materials. This value could be calculated by the 'Oxygen Consumption Method' under various producing irradiances to each surface of materials. In this study, Process of the cone calorimeter test was simulated by Pyrolysis model of FDS (Fire Dynamics Simulator by NIST) base on the ISO 5660 international standard. Then, we could estimate the simulation method of FDS in case of single materials through the comparative study with test results.

• International Journal of Concrete Structures and Materials
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• v.19 no.1E
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• pp.25-32
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• 2007

The fracture energy evaluated from the previous experimental results can be simulated by using the modified singular fracture process zone (S-FPZ) model. The fracture model has two fracture properties of strain energy release rate for crack extension and crack close stress versus crack width relationship $f_{ccs}(w)$ for fracture process zone (FPZ) development. The $f_{ccs}(w)$ relationship is not sensitive to specimen geometry and crack velocity. The fracture energy rate in the FPZ increases linearly with crack extension until the FPZ is fully developed. The fracture criterion of the strain energy release rate depends on specimen geometry and crack velocity as a function of crack extension. The behaviors of micro-cracking, micro-crack localization and full development of the FPZ in concrete can be explained theoretically with the variation of strain energy release rate with crack extension.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.1
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• pp.170-180
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• 1995

A parallel crack in bonded dissimilar orthotropic planes under out-of-plane loading is analyzed. The problem is formulated by Fourier integral transforms, and reduced to a pair of dual integral equations. By solving the integral equations, the asymptotic stress and displacement fields near the crack tip are determined in closed form, from which the stress intensity factor and energy release rate are obtained. Discontinuity in the stress intensity factor as the distance ratio h/a of the parallel crack approaches zero is found, while the energy releas rate is shown to be continuous at h/a = 0. This information can immediately be used to generate the stress intensity factor for the parallel crack near the interface. By employing "the maximum energy release rate criterion", it could be shown in the case of no existing crack initially that the parallel crack is formed far from the interface for the more compliant material, while it is formed close to the interface for the stiffer material. material.